27 Foods To Cure The 'Invisible Deficiency' Affecting 50% Of Americans

When you need a dose of vitamin C, you know to go for the citrus. Or to cook up some spinach or steak when you need to load up on iron. But what foods should you turn to when you’re low in magnesium, and how can you tell if you're deficient?

If you find yourself easily irritable, tired, or weak, you may be low in this essential mineral. Magnesium is crucial to more than 300 bodily functions, including those affecting the heart, bones, muscles, and nervous system. If left untreated, chronic lack of magnesium in the body can lead to seizures or abnormal heart rhythms.

Despite its importance, magnesium deficiency has become increasingly more prevalent, currently affecting about half of the population. It’s recently been named the “invisible deficiency” by many experts, as symptoms are fairly general and the deficiency itself is hard to diagnose.

Related: Is This the New Iron Deficiency?

So why are so many people slacking in the magnesium department? Consuming diets high in processed foods instead of fresh veggies, whole grains, seeds, and fish is a big factor, says nutritionist Keri Glassman, MS, RN, CDN, founder of Nutritious Life.

Getting your recommended daily intake of magnesium — 400 to 420 milligrams for men and 310 to 320 milligrams for women – is easiest and most efficient by incorporating whole foods with high levels of magnesium into your daily meals.

Glassman recommends eating as clean of a diet as possible, including lots of beans, nuts, and green, leafy vegetables — even seaweed, which packs 67 milligrams of magnesium in just one cup.

Related: How Your Body Signals That You're Vitamin Deficient

It's smart to also monitor where your food and water comes from. “Many foods are also depleted of their natural magnesium levels because our water supply is lacking in magnesium and minerals in the soil just aren’t what they used to be, affecting how the food is grown,” she tells Yahoo Health.

The highest levels of magnesium from water come from deep wells, but urban sources of drinking water (the most popular for bottled and tap water) are taken from surface water, where magnesium is low, says Glassman.

While diet is the No. 1 way to increase your magnesium levels, if you are having difficulty, it's best to consult a physician before taking supplements.

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